Ti_70-xTa₁₅Zr₁₅Fe_x (x=0.3、0.6、1.0)形状记忆合金薄膜的马氏体相变与阻尼行为

In recent years, there has been a rapid development in microelectromechanical systems owing to their lightweight and integration with small volume. The microactuater bears low-frequency vibrations during operations, which affects the safety and stability of the device. Ti-Ta-Zr-Fe thin film is a high-temperature shape memory alloy film, which has good shape memory effect and thermal stability. The addition of Fe can improve the plasticity of the film and make it promising to use in high-temperature miniature damping devices. Ti_70-xTa₁₅Zr₁₅Fe_x (x=0.3, 0.6, and 1.0, atomic fraction, %) shape memory thin films were prepared by direct-current magnetron sputtering. The effect of the Fe content on the microstructures, martensitic transformation, mechanical properties, and damping behavior was studied by XRD, TEM, bending test, and dynamic mechanical analysis. It was found that the room-temperature phase composition of the alloy films with different Fe contents were in the parent and martensite phases. The reverse martensitic transformation temperature of the thin films was above 100 ℃, and the films exhibited the two-way shape memory effect. The addition of Fe enhanced the ductility and strength of the film. When the Fe content was 1.0%, the elongation could reach up to 12.8%. During the heating and cooling processes, the relaxation type friction peak was observed. The damping capacity during the relaxation processof the film containing 1.0%Fe could reach up to 0.116.